Fuel Design

The fuel design of the Super LWR follows that of LWRs [30]. UO2 is used for fuel pellets. Stainless steel and Ni-base alloy are the candidate cladding materials. 

Its fuel rod design also follows that of LWRs. The failure modes of fuel rods considered are over-heating, pellet cladding mechanical interaction (PCMI), buckling collapse, and creep rupture at both normal and abnormal transients. 

The four basic design criteria in the fuel rod design are as follows, for both normal and abnormal transients  

In LWRs, buckling collapse and creep rupture are not included in the design failure modes, because experimental verifications have shown that these failure modes are not limiting as long as the plastic deformation of the fuel rod is less than 1.0%. The core pressure and temperature of the Super LWR are much higher than those in LWRs, so these failure modes need to be included in the design failure modes. The evaluations of stresses on the cladding are based on ASME Boiler and Pressure Vessel Code Section III as adopted in BWRs for simplified evaluations. 

In BWRs, all stresses (pressure difference, hydraulic vibrations, contact pressure of spacers, etc.) are first evaluated and categorized into primary membrane stress, primary bending stress, and secondary stress. The maximum allowable stresses are set for each of these categorized stresses at both normal and abnormal transients. The maximum allowable stresses in the Super LWR fuel rod design are determined similarly. 

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MO fuel designed for use in existing LWRs is typically exposed to bum-ups greater than 40 x 10 MW-d/t. The discharged MO fuel has essentially the same uranium enrichment as uranium oxide fuel, but has a greater total amount of plutonium. 

The fuel designations in the above surveyed data were determined by the fuel that contributes the most Btu for power generation during the survey. 

Figure 6-22 Hydrogen requirements for heavy fuel (designated sulfur content) production from various feedstocks.

Mochida, I., Sakanishi, K., Ma, X.L., Nagao, S., and Isoda, T. Deep hydrodesulfurization of diesel fuel Design of reaction process and catalysts. Catalysis Today, 1996, 29, 185. 

These considerations will influence the choices made as the industry plans its products in a shifting market and policy context. Not all factors are equally important at a given point in time, and so their relative emphasis also determines the choices made. Any option for future vehicle fuel design, including a default slow evolution of existing technology, must compete in order to command the substantial investments entailed in both product development and infrastructure provision. 

Cochran, R. Tsoulfanidis, N. Fuel design and fabrication. In The Nuclear Fuel Cycle Analysis and Management] American Nuclear Society LaGrange Park, IL, 1999 77-104. 

The Subcommittee on Permissible Exposure Levels for Military Fuels found that data on potential nervous system effects of jet fuels are sparse. In several Swedish studies conducted by Knave and his colleagues, acute CNS symptoms were reported in workers who were employed in jet factories where they were potentially exposed to jet fuels designated Jet A-l andJP-1 (Knave et al. 1976, 1978, 1979). Industrial-hygiene measurements of up to 3,200 mg/m3 were reported for a variety of job activities. Although the one-time air measurements reflected various activities, the exposures were not well characterized over time or by individual. 

CFC replacements PCB replacements degradable pesticides, polymers cleaner fuels designer compounds... 

The shale oil derived jet fuel (designated Shale-I) used in this work was produced from a crude shale oil (supplied by Paraho, Inc.) by delayed coking, fractionation, and mild hydrotreatment at the Gary-Western refinery. The entire production operation has been fully described elsewhere ( 3). The physical properties of the jet fuel have been reported (1). 

The reference fuel design, quality, performance models, and methods discussed in Section 4.2.5.2.2.3 were used to calculate the fuel particle failure and the gaseous and metallic fission product releases as a function of time. The key attributes for fuel quality are summarized in Table 4.2-4 and the design is in Table 4.2-16. The following fuel particle failure mechanisms were considered in the analysis ... 

Qualified MOX fuel designers FRAGEMA, SIEMENS, TOSHIBA/HITACHI/JNF, BELGONUCLEAIRE... 

Fig. 5 HTR-MODUL fuel design data, release versus temperature, mechanisms of the release, and THTR-300 ftiel data From these data it is concluded, that the core-outlet temperature can be increased to 1 050 °C for future HTRs with modem gas turbine technology.

Adequate performance of the cooling systems should be determined by the fuel design limits. 

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